That is exactly the point I was (sleepily) trying to make: I'd guesstimate that 9 in 10 of the folks on forums that say "my copy of lens X is sharper than lens Y, I've tested them both" didn't actually calibrate their AFMA before they did their "testing", and it's awfully rare that anyone mentions that they actually *did* check AFMA beforehand. The same likely goes for people returning lenses because they got a "bad copy"...

That is exactly the point I was (sleepily) trying to make: I'd guesstimate that 9 in 10 of the folks on forums that say "my copy of lens X is sharper than lens Y, I've tested them both" didn't actually calibrate their AFMA before they did their "testing", and it's awfully rare that anyone mentions that they actually *did* check AFMA beforehand. The same likely goes for people returning lenses because they got a "bad copy"...

The diff between 0 and +1 by 12points(880 vs 892, x50 in distance) through Reikan FoCal, I wonder the human can see this diff? I rather leave my @ zero

In my opinion the 100L is better than the 135L at everything, except that the 135L is F2 one extra stop a more creamy bokeh. No Macro capibility on the 135L though. They are both super sharp. Here is a shot a took today with the 100L

The diff between 0 and +1 by 12points(880 vs 892, x50 in distance) through Reikan FoCal, I wonder the human can see this diff? I rather leave my @ zero

Perhaps not. But AF systems aren't perfect - take a bunch of shots, and while a properly AFMA'd lens will result in spot-on focus on average, any given shot may be a bit off. By ensuring the AFMA is correct, you're ensuring that the shots that are a bit off are less off.

To OP - it all comes down to personal choice. Some prefer a 100mm look and others like the longer 135mm look. Both lenses are sharp, both are excellent. If you think you might need macro capability then your choice is simple. If portraits and indoor sports is your thing then the 135 is a clear winner.

With regards to wide open performance - the 100 may be sharper wide open at f/2.8 but remember the 135 f/2 is super sharp once it's stopped down. So if you were to compare both @ f/2.8 then the 135 (probably) has the advantage.

There's something else about the 135 that gives you this special kind of look. I dunno if it's bokeh or the clarity or how it handles colors but it all comes together nicely. Then again maybe the 100L has that look?

That is exactly the point I was (sleepily) trying to make: I'd guesstimate that 9 in 10 of the folks on forums that say "my copy of lens X is sharper than lens Y, I've tested them both" didn't actually calibrate their AFMA before they did their "testing", and it's awfully rare that anyone mentions that they actually *did* check AFMA beforehand. The same likely goes for people returning lenses because they got a "bad copy"...

My 135 has always needed +2 AFMA, whether it was on the 50D, the 1D4, or the 6D.

Frankly, if 9 out of 10 people are not doing AFMA, that is one sorry state of affairs! They have no business buying this equipment if they can't use it correctly.

Certainly not all lenses need AFMA adjustment...

Logged

canon rumors FORUM

Sorry to say, but actual lens sharpness has nothing to see with AFMA. AFMA is to calibrate the precision of the AF camera / lens combination. If a lens is not sharp in AF mode, it's because of the camera / lens combination, it says nothing about the real sharpness of the lens, though it will of course give a sharper image in AF mode when the AFMA is properly adjusted.

A lens can be extremely sharp and show poor results because of a bad AF adjustment, but the same lens focused manually will show perfect results (unless defective). If you want to compare lens sharpness, the only way is a solid tripod, a powerful steady light source (or flash) and manual focusing with x10 magnification on live view. If you test your lens in AF, you test the AF ability with one specific lens, not the optical sharpness of the lens.

Sorry to say, but actual lens sharpness has nothing to see with AFMA. AFMA is to calibrate the precision of the AF camera / lens combination. If a lens is not sharp in AF mode, it's because of the camera / lens combination, it says nothing about the real sharpness of the lens, though it will of course give a sharper image in AF mode when the AFMA is properly adjusted.

A lens can be extremely sharp and show poor results because of a bad AF adjustment, but the same lens focused manually will show perfect results (unless defective). If you want to compare lens sharpness, the only way is a solid tripod, a powerful steady light source (or flash) and manual focusing with x10 magnification on live view. If you test your lens in AF, you test the AF ability with one specific lens, not the optical sharpness of the lens.